This commit fixes a bug in the **View Engine** implementation of
`getSemanticDiagnostics` and `getDefinitionAndBoundSpan` for node in the
decorator metadata that represents an external URL
(`templateUrl` or `styleUrls`).
The URL could be either relative or absolute, but the latter was not taken
into account.
Fix https://github.com/angular/vscode-ng-language-service/issues/1055
PR Close#40406